package org.apache.lucene.index;

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements. See the NOTICE file distributed with this
 * work for additional information regarding copyright ownership. The ASF
 * licenses this file to You under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

class SegmentTermPositionVector extends SegmentTermVector implements
		TermPositionVector {
	protected int[][] positions;
	protected TermVectorOffsetInfo[][] offsets;
	public static final int[] EMPTY_TERM_POS = new int[0];

	public SegmentTermPositionVector(String field, String terms[],
			int termFreqs[], int[][] positions, TermVectorOffsetInfo[][] offsets) {
		super(field, terms, termFreqs);
		this.offsets = offsets;
		this.positions = positions;
	}

	/**
	 * Returns an array of TermVectorOffsetInfo in which the term is found.
	 * 
	 * @param index
	 *            The position in the array to get the offsets from
	 * @return An array of TermVectorOffsetInfo objects or the empty list
	 * @see org.apache.lucene.analysis.Token
	 */
	public TermVectorOffsetInfo[] getOffsets(int index) {
		TermVectorOffsetInfo[] result = TermVectorOffsetInfo.EMPTY_OFFSET_INFO;
		if (offsets == null)
			return null;
		if (index >= 0 && index < offsets.length) {
			result = offsets[index];
		}
		return result;
	}

	/**
	 * Returns an array of positions in which the term is found. Terms are
	 * identified by the index at which its number appears in the term String
	 * array obtained from the <code>indexOf</code> method.
	 */
	public int[] getTermPositions(int index) {
		int[] result = EMPTY_TERM_POS;
		if (positions == null)
			return null;
		if (index >= 0 && index < positions.length) {
			result = positions[index];
		}

		return result;
	}
}